Recent content by jgiarrusso

  1. J

    Solving Initial Value Problem with Implicit Solution

    Homework Statement Solve the initial value problem (y+e^-y)y'=sinx subject to y(pi)=0 Homework Equations The Attempt at a Solution I'm not quite sure what to do with this one. I've scanned through my book and could find no similar problems in what we've done so far. I tried to...
  2. J

    Diff EQ Intro - Verify Family of Functions as Solution

    So then dy/dx would be: dy/dx = e-x2 * ex2 - 2xe-x2\int(from 0 to x)et2dt - 2xc1e-x2 And then plugging it into the differential equation, it all cancels out. Thank you so much!
  3. J

    Diff EQ Intro - Verify Family of Functions as Solution

    Homework Statement Verify that the indicated family of functions is a solution of the given differential equation. Assume an appropriate interval I of definition for each solution. Homework Equations dy/dx + 2xy = 1; y = e-x2\int(from 0 to x)et2dt + c1e-x2 The Attempt at a Solution...
  4. J

    Finding the Arc Length of a Polar Function

    Thanks! That's what I get for trying to do my homework far too late at night and without my list of identities nearby ~_~
  5. J

    Finding the Arc Length of a Polar Function

    Hmm, that did allow me to solve the integration (at least, I think I did it properly). But now, when I go to plug in my evaluation, I'm getting sec(π/2) which is doesn't work out. Using the half angle, I got (1-cosθ)=2cos2(θ/2). Plugging that in canceled out my 2sqrt2, and made the...
  6. J

    Finding the Arc Length of a Polar Function

    Aha, thank you so much. That was just the push I needed!
  7. J

    Finding the Arc Length of a Polar Function

    Hi, I've been having some issues in solving this problem. Homework Statement Find the arc length of r=2/(1-cosθ) from π/2 to πHomework Equations L =(integrate) sqrt(r2+(dr/dθ)2)dθ The Attempt at a Solution I found (dr/dθ) = (-2sinθ)/(1-cosθ)2 so (dr/dθ)2 = (4sin2θ)/(1-cosθ)4 Then r2 =...